Blowing in the Wind: Beijing’s New Cleanup Plan for Bad Air

A woman wears a mask as she rides her bicycle along a street near Tiananmen Square in Beijing on on Dec. 21, 2015, the third day of a red alert for pollution.

Agence France-Presse/Getty Images

Half a millennia ago, China’s emperor constructed a large marble altar in Beijing for ceremonies to propitiate the sun. These days, though, residents of the capital are far more likely to pray for something else: the wind.

While many days Beijing sits in a smoggy haze, a few fierce gusts of wind can turn the sky a startling hue of blue. Beijingers may be wishing for more of it.

The country’s environmental minister recently announced plans to unify the standards Beijing and surrounding areas use to declare emergency measures to reduce smog. The upshot: the threshold for triggering a smog alert in the capital is being raised.

While residents have criticized the Beijing government in the past for failing to hoist red alerts amid choking levels of smog, the city issued two late last year during particularly nasty bouts of pollution. The red alerts trigger a series of measures to reduce pollution, including ordering half the cars off the roads, shutting down factories and halting school classes.

The new system attempts to tackle Beijing’s bad-air problem as part of the wider pollution afflicting the surrounding area, including Tianjin and four other cities in neighboring Hebei province. The area persistently experiences some of China’s worst pollution levels, thanks to a concentration of heavy industry.

Under the previous system, Beijing would issue a red alert when the air quality index, which measures various pollutants, exceeds 200 for more than three days. In the new system, red alerts will be issued when AQI is forecast to rise above 500 for a day or more or when the AQI forecast is expected to exceed 200 for four days or 300 for two days or more.

That Beijing needs better pollution control measures and more creative thinking on the problem isn’t in question. The city has launched numerous initiatives to tame its smog, from moving heavy industry out of the city to periodically ordering cars off the street and banning outdoor barbecue.

Beijing on a windy day, a photo taken on Dec. 1, 2015. The day before, air pollution levels had reached the maximum on the governments official index, which tops out at 500.

Te-Ping Chen/The Wall Street Journal

The effort has paid noticeable dividends: in the first half of last year, levels of PM2.5 — the fine particulate matter hazardous to human health — dropped 16%, compared to the same period in 2014. But November’s and December’s heavy pollution offset those improvements. By the year’s end, the annual average concentration of such pollutants had fallen by only 6%, according to the environmental ministry.

Ma Jun, founder of the nongovernmental Institute of Public & Environmental Affairs, said it made sense to unify the smog-alert standards. For Hebei, he said, the common standard will mean a quicker triggering of action.

But he criticized the move’s impact on Beijing. “There are legitimate concerns about such high social and economic costs of red alerts, concerns not just only from officials but also from residents,” said Mr. Ma. “But on the other hand, there’s a very strong need to protect the health of the people, especially the young and vulnerable,” he said, calling any weakening of such protections “most regrettable.”

Hence the city’s need for more wind. In another effort to clear up its skies, the city is planning to construct channels to speed passage of the wind through the city, official news agency Xinhua reported over the weekend.

These corridors will be created by linking various parks, roads and other natural features in the city to allow for better ventilation, the agency said. Five will be 500 meters or wider while the more than 10 other planned corridors will be narrower, the agency reported, citing the Beijing municipal commission of urban planning.

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